Telephone system for railroads



Dec. 1, 1931. J. B. DAVIS TELEPHONE SYSTEM FOR RAILROADS Filed April 29, 1930 the telephone system Patented Dec. 1, 1931 JOE B. DAVIS, OF LOS ANGELES, CALIF RNIA mmnonn srsrm ron nan-mans Application died A ril 29, 1930. Serial mus cs] My invention relates to a tele hone system for railroads and the principa object is to provide electrical means constructed and arranged 'so that conversation may be carried on etween persons traveling on the railroad and others at stations along the railroad or other places; and also so that mes sages can be delivered or transmitted to or from the railroad trains, or from train to train, while in motion.

The object of my invention is to providea permanent and inexpensive telephone system that can be easily installed in new or railroads now in use .and connected to the trains and to stations along the railroad and with telephone instruments of conventional type arranged in the system so that communications can be had between persons on the trains and in the stations and from train to train.

Another object of my invention is to provide the system with an electrical circuit eon tact mechanism for each car of a railroad train adapted to automatically and continuously keep the circuit between the car and station closed to permit an uninterrupted conversation to be held between persons on and ed the train while it is in motion.

The accompanyin drawin illustrate the invention in a simp e form, it being understood that a telephone system for a railroad includes many trains and stations, only one of each bein shown in the drawings and described in 51s specification for the sake of brevity.

Fig. 1 is across sectional elevational view through a car showingx the circuit contact mechanism of the telep one system connecting the telephone instrument with the circuit.

wire. I o i Fig. 2 is a top view of the contact. mechanism showing t e means connecting it to the car.

Fig. 3 is a fragmental end view of the car showing a side view of the circuit contact mechanism.

Fig. 4 is another view of the circuit contact as viewed from the side of the car.

Fig. 5 is a diagrammatical planview 0 showing one circuit -tically tocompensate wire, one train and one station connected "so that conversation can be held from the station to the moving train and vice versa.

The telephone system includes an electrical contact mechanism 2 for each car or train of a railroad, it bein understood that there are many trains,'e ac equipped with means for telephoning to stations along the railroad. The mechanism 2 is connected to the car 6 and is insulated therefrom by the late 8 and also connected to the telephone instrument 10, as will be explained later. The

mechanism includes a bar 12 that is'bolted to the car, as at 14, and has a movable arm 16 pivotally connected by a bolt 20 to the bar 12. The outer end of the arm 16 is turned downward to form a pivotal point for the frame 22 and is connected to it by a pin 24. The frame 22 includes the spaced han ers 28 carrying a bearing pin 30 on whic a contact roller 26 is mounted so it can 7 freely rotate.

The rail cross ties 32 are used to support the insulated posts 34: and screwed into the upper ends of these posts are the ears 38 in w oh the circuit line wire 36 is secured and the railroad at a predeterextended along and fixed distance from the mined elevation track.

. The roller 26 is the linewire 36 by a spring 40 that has one end secured to the bar 12 and its other end under tension on the arm 16 arranged so that the roller has'considerable play verfor unevenness 1n the height of the line wire 36, also the roller 26 is elongated to compensate for the rocking of the train while in motion. Also a sa ety stop 42 is secured on the underside of the bar 12 and is arranged to limit the downward movement of arm 16 so that in the event the wire 36 should be broken the roller 26 will not catch on the posts 34 and injure the contact mechanism.

A telephone instrument 10 can be arranged held in light contact with t in an suitable place in the car 6 and com necte to the contact mechanism 2 by the wire 54. The telephone has the usual ref ceiver book 56 for placing it in operation to receive or send a message and the curnism, enables persons on rent passes to the ground 60 through the wire 58. It is understood that there can be a telephone in each car of a train if desired and arranged to telephone from one car to another or from one train to another or to the stations alon the railroad whereby b means of switch ards not shown but we own in the art the telephones on the moving trains can be placed in communication with ofiices and dwellings remotely located relative to the railroad.

Electrical current is supplied to the wire 36 in the usual we as indicated by the motor in Fig. 5, which is assumed to be at a station adjacent the railroad track and which can be connected in the usual way to the line wire 36.

The stations along the railroad are provided with telephone instruments similar to those on the train, and also can have the usual telegraphic instrument 52 for the usual communications between railroad stations.

In operation I provide each train as previously stated with tele hone instruments which, through the electrical contact mechaa moving train to communicate with persons in the railroad stations or remote places while the trains are in motion or traveling over the railroad.

While I have described my invention in view of the drawin which are shown partly diagrammatical y and for the purpose of illustration, it is obvious that the mechanism employed can be modified throughout a wide ran e and I reserve the right to make such modi cations as fall within the scope of the appended claims.

I claim as my invention:

. 1. In a telephone system the combination 'with a line wire, a stationary telephone in circuit with said wire, of a telephone on a train, a bar carried by said train, a wire connection between said bar and telephone, an arm pivotally connected to said bar, a frame carried by said arm, a roller carried by said frame arranged to engage said line wire so as to close the circuit between said telephones, and a spring on said bar for engaging said arm so as to hold said roller in yielding contact with said line wire.

2. In a telephone system the combination with a line wire, a stationary telephone in circuit with said wire, of a telephone on a train, a bar carried by said train, a wire connection between said bar and telephone an arm piv otally connected to said bar, a i rame carried by said arm, an elongated roller carried by said frame arranged to engage said line wire so as to close the circuit between said telephones, 9, spring on said bar for engaging said arm so as to hold said roller in yielding contact with said line, and a stop on said bar for limiting the movement of said arm toward said line wire.

3. In a telephone system the combination with a line wire supported on posts arranged parallel with a railroad track telephone in circuit with said line wire, of a telephone on a train adapted to travel over the railroad track, a bar insulated from but carried by the train, a wire connecting said bar to the telephone on the train, an arm pivotally connected to said bar and extended out over said line wire, a frame carried by said arm, an elongated roller carried by said frame arranged to engage said line wire and close the circuit between said telephones, a spring on the upper side of said bar arranged to engaged said arm and hold said roller in yielding contact with said line wire, and a stop arranged on the underside of said bar for limiting the movement of said arm toward said line wire.

4. In a telephone system for a railroad the combination with posts arranged on the cross ties of a railroad adjacent the ends thereof,

posts, a circuit line Wire arranged on and secured to said cars and extended parallel with said railroad, a stationary telephone in circuit with said line wire, another telephone on a train on said railroad that can also be placed in circuit with said line wire, a motor for supplying current to said line wire and telephones, of a bar secured to and insulated from said train, an arm having one end pivotally connected to theouter end of said bar, a frame pivotally connected to the other end of said arm, an elongated roller carried by said frame for engaging said line wire, said parts mounted and arranged to compensate for unevenness in said line wire and rocking movement of said train when traveling, and an electrical connection from said bar to the telephone on said car, whereby a circuit is established between said telephones so a person on the moving car can communicate with a person at said stationary telephone.

In testimony whereof I have signed my name to this specification.

JOE B. DAVIS.

, a stationary 

